The present invention relates generally to doorbells and, in particular, to an apparatus for wireless communication with remotely located auxiliary doorbell chimes.
Many devices for generating remote signals are known. The U.S. Pat. No. 4,430,652 shows a remote control system for causing an audible signal to be produced at a remote location. The system includes a manual signal switch that causes a transmitter to produce a manually encoded radio frequency signal, which signal is received by a receiver. The receiver is coupled with signal decoding and processing circuitry to appropriately operate a signalling device, such as a whistle typically used in the logging industry.
The U.S. Pat. No. 4,523,193 shows a radio frequency transmitter that communicates with a remote receiver. The transmitter is wired across a doorbell and is activated when power is applied to ring the doorbell.
The U.S. Pat. No. 4,912,463 shows a remote control apparatus having a transmitter and a receiver. The transmitter communicates with the receiver by a radio frequency signal, which signal can be varied according to the position of a switch in the transmitter. The position of the switch dictates the mode of operation of the transmitter. The transmitter is activated by a push button switch.
The U.S. Pat. No. 3,017,623 shows a doorbell and porch light control circuit for turning on a porch light at the same time as activating a doorbell. When the doorbell button is pressed, a circuit is closed and the doorbell chime is activated. A relay coil is energized, which causes a relay switch to move into contact with a lead. Once the switch contacts the lead, the circuit for energizing the light is closed and the light turns on. A bi-metal operated switch is shown that acts as a timer for eventually turning off the power to the light a selected amount of time after the doorbell button was pressed.
The present invention concerns an apparatus for activating a doorbell chime and for remotely controlling an auxiliary doorbell chime. The apparatus includes a push button unit adapted to be connected to a doorbell chime and a source of electrical power and being responsive to manual actuation for activating the doorbell chime from the source of electrical power and for generating a radio frequency wave and a remote unit being responsive to the radio frequency wave for generating an auxiliary acoustic frequency wave representing manual actuation of the push button unit.
The push button unit has a manually actuated switch assembly with a first pair of normally open switch contacts adapted to be connected in series with the doorbell chime and the source of electrical power and a second pair of normally open switch contacts, a radio frequency transmitter connected in series with the second pair of contacts, the second pair of contacts and the radio frequency transmitter adapted to be connected in series with the doorbell chime and the source of electrical power for generating a radio frequency output signal at an output of the transmitter and a first antenna connected to the transmitter output and being responsive to the radio frequency output signal for generating the radio frequency wave. The remote unit has a second antenna responsive to the radio frequency wave for generating a radio frequency input signal, a radio frequency receiver having an input connected to the second antenna and being responsive to the radio frequency input signal for generating a generator activation signal and an acoustic generator having an input connected to the receiver output and being responsive to the generator activation signal for generating the auxiliary acoustic frequency signal.
The acoustic generator can be a speaker for generating the auxiliary acoustic frequency wave. Furthermore, the push button unit can include a power supply connected across the first pair of contacts for receiving charging current and having a power output, the radio frequency transmitter can have a power input connected to the power output and an activation input connected to one contact of the second pair of contacts, and another contact of the second pair of contacts can be adapted to be connected to the source of electrical power whereby the power source provides power for generating the radio frequency output signal.
The apparatus according to the present invention has the advantage that it replaces the existing doorbell and does not require any other electrical connection to the existing doorbell chime.